1. Field of the Invention
The present invention relates generally to a tub grinder type of machine and, more particularly, is concerned with a toothed plate adapted to be used in the tub grinder machine for facilitating disintegration of crop material clumps by the hammermill grinding mechanism of the machine.
2. Description of the Prior Art
In recent years, tub grinder machines have been realizing considerable commercial acceptance, particularly, by large cattle feeding and dairy operations where substantial volumes of ground forage products are utilized on a daily basis as feed for livestock.
The tub grinder machine conventionally has a mobile frame, a crop material receiving tub mounted on the frame, a hammermill type grinding mechanism mounted below the tub and a conveyor for discharging crop material ground by the hammermill from the machine. The tub includes a bottom wall stationarily mounted on the frame and a generally upright cylindrical side wall bounding the periphery of the bottom wall. The side wall is mounted for rotation about a generally vertical axis relative to the stationary bottom wall. The bottom wall has an opening formed therein between the pheriphery and center thereof. The hammermill grinding mechanism is mounted below the opening and includes a concave screen, a rotatably mounted shaft and a plurality of radially-extending, axially-spaced hammer elements operatively mounted thereon. The hammer elements move in generally circular paths projecting upwardly through the opening upon rotation of the shaft so as to engage and grind crop material being moved about the bottom wall and delivered to the opening therein as the side wall of the tub is rotated. The material ground by the hammer elements is discharged through the concave screen to the conveyor which is operable to deliver the ground material to a storage area or livestock feeding location as desired.
The tub grinder machine must be able to process forage crop materials which vary widely in texture, consistency, moisture content and other characteristics. Frequently, large clumps of material are present in the bulk of material dumped in the tub of the machine for grinding and when such clumps are encountered by the hammermill mechanism, they are apt to overload the same and sometimes jam and stall out the mechanism completely.
For facilitating disintegration of crop material clumps, one recent version of the tub grinder machine, such being described and illustrated in U.S. Pat. No. 3,743,191 to Robert R. Anderson dated July 3, 1973, has a series of spaced apart stationary plate-like hammers fixed upon and projecting in parallel vertical planes outwardly from an elongated plate mounted along the crop material receiving edge of the opening to the hammermill formed in the bottom wall of the tub.
Another recent version of the tub grinder machine, such being described and illustrated in U.S. Pat. No. 3,966,128 to Joseph A. Anderson et al dated June 29, 1976, has a feed control plate mounted along the crop material receiving edge of the opening to the hammermill formed in the bottom wall of the tub for movement by manual adjusting linkage between various positions which regulate the size of the opening to the hammermill and thereby control the amount of crop material which can be delivered to the hammermill at any one time.